A high-dynamic range (HDR) image, compared with an ordinary image, may provide more image details of a larger dynamic range. Currently, in the HDR solution, multiple images having different exposure time lengths are captured continuously and synthesized, and the multiple images captured continuously are generally completed serially, that is, only after exposure of a current image is completed, capture of a next image begins to be performed, and therefore, a total HDR image capture time is accumulation of respective exposure time lengths corresponding to multiple images.